Unable to deliver the message due to a communications failure

Posted on 2003-11-20
Last Modified: 2007-12-19
I'm the network admin to a corp. and the problem I'm having is I'm able to send email through or exchange 5.5 server but certain email addresses when sent to are unable to delivered. I checked to see if we have a reverse dns and it has been added since we didn't have one through our ISP any more info need please let me know
Question by:randtaraad
  • 7
  • 3
  • 2
  • +1

Author Comment

ID: 9791934
Thanks ... sorry I'm new to this forum.

Expert Comment

ID: 9797527
This sounds like DNS issue. If U are using Exchange server 5.5, make sure U are using good and reliable DNS.
and I would check to see if your domain is open to relay. Please check to see if your domain is on the blacklist.

Let me know if U need how to check if the dns you r using is reliable dns

good luck


Author Comment

ID: 9801376
if you wouldn't mind giving me some tips that would be very helpful. I kinda figured that it could be a dns. Issue like I said I checked for a reverse DNS since some email servers won't accept email with out one but the funny thing is that it worked a couple of weeks ago just find I tried to trace where the problem was but I can't seem to find it we have 2 servers running nt server one the wins and exchange server the other the DNS and file server ... thanks
Are your AD admin tools letting you down?

Managing Active Directory can get complicated.  Often, the native tools for managing AD are just not up to the task.  The largest Active Directory installations in the world have relied on one tool to manage their day-to-day administration tasks: Hyena. Start your trial today.


Expert Comment

ID: 9801405

start>run> and type cmd and ENTER
at the command prompt type

nslookup ENTER
type this " Server space the external DNS server U using

i.e server then enter
set q=mx ENTER

type the domain you are sending the email to ..

It should resolve to their MX record

If it does not work, then you have DNS issues


Author Comment

ID: 9801609
if that doesn't work what do you think could be wrong with the DNS?

Expert Comment

ID: 9801622
is there anyway you can put in the entire failure message?

Alot of anti-spam servers poping up around the net... might be something from one of them.

Author Comment

ID: 9802000
>  -----Original Message-----
> From:       System Administrator  
> Sent:      Thursday, November 20, 2003 3:15 PM
> To:      ''
> Subject:      Undeliverable: test

> Your message did not reach some or all of the intended recipients.

>       Subject:      test
>       Sent:      11/20/2003 3:15 PM

> The following recipient(s) could not be reached:

>       '' on 11/20/2003 3:15 PM
>             Unable to deliver the message due to a communications failure
>       The MTS-ID of the original message is: c=US;a= ;p=Romeo
> RIM;l=SIDEWINDER-031120201430Z-94


Author Comment

ID: 9802004
I tried emailing it from other workstations and also from home I can email from home through my email at Atumus but I can't through my work email nor can any other employee in side the building

Expert Comment

ID: 9802039
These are the mail servers for that domain:      21600       MX  5      21600       MX  5      21600       MX  5      21600       MX  5      21600       MX  5

Ok, do this, from your work email server:

C:\telnet 25

You will connect, but it takes a minute for their server to respond for some reason, probably to delay spammers.

Next do this, it will respond after each command, so pay attention to what it says:

helo user
mail from: <>
rcpt to: <>
some text or whatever you want to type... i like to bang on the keyboard or type test then you do a dot on a single line by itself like so

At this point it should say mail queued for delivery.  Being your are having issues, i bet you dont make it to this point.

Accepted Solution

ydirie earned 500 total points
ID: 9802488
Check your Event log, you should be getting warning errors. Please send me what the errors are.

here another article that talks about it

When you ping your own server, what does it respond to? Does it respond to

ping test


ping test

test (the IP address)

your exchange server NIC card DNS settings, what are the orders of your DNS server

Internal DNS followed by external DNS or vise versa

This is all I am assuming you have one exchange server

your problem is nothing but lasy DNS somewhere...please do these tests above and let me know

Author Comment

ID: 9806215
thanks for your help so far I'm going to try and see where it all leads I'll keep you posted thanks for your help thus far

Author Comment

ID: 9824534
thanks for all your help guys I'm glad I finally have this issue solved

Expert Comment

ID: 10889669
Hey I am having the same exact problem, how did he resolve the problem?

Featured Post

Free eBook: Backup on AWS

Everything you need to know about backup and disaster recovery with AWS, for FREE!

Question has a verified solution.

If you are experiencing a similar issue, please ask a related question

Suggested Solutions

We are happy to announce a brand new addition to our line of acclaimed email signature management products – CodeTwo Email Signatures for Office 365.
This article lists the top 5 free OST to PST Converter Tools. These tools save a lot of time for users when they want to convert OST to PST after their exchange server is no longer available or some other critical issue with exchange server or impor…
In this video we show how to create a Shared Mailbox in Exchange 2013. We show this process by using the Exchange Admin Center. Log into Exchange Admin Center.: First we need to log into the Exchange Admin Center. Navigate to the Recipients >> Sha…
This video demonstrates how to sync Microsoft Exchange Public Folders with smartphones using CodeTwo Exchange Sync and Exchange ActiveSync. To learn more about CodeTwo Exchange Sync and download the free trial, go to:…

685 members asked questions and received personalized solutions in the past 7 days.

Join the community of 500,000 technology professionals and ask your questions.

Join & Ask a Question